const marked = require('marked');

const renderer = new marked.Renderer();
const Prism = require('node-prismjs');

const insideString = {
  variable: [
    // Arithmetic Environment
    {
      pattern: /\$?\(\([\w\W]+?\)\)/,
      inside : {
        // If there is a $ sign at the beginning highlight $(( and )) as variable
        variable   : [{
          pattern   : /(^\$\(\([\w\W]+)\)\)/,
          lookbehind: true
        },
          /^\$\(\(/,
        ],
        number     : /\b-?(?:0x[\dA-Fa-f]+|\d*\.?\d+(?:[Ee]-?\d+)?)\b/,
        // Operators according to https://www.gnu.org/software/bash/manual/bashref.html#Shell-Arithmetic
        operator   : /--?|-=|\+\+?|\+=|!=?|~|\*\*?|\*=|\/=?|%=?|<<=?|>>=?|<=?|>=?|==?|&&?|&=|\^=?|\|\|?|\|=|\?|:/,
        // If there is no $ sign at the beginning highlight (( and )) as punctuation
        punctuation: /\(\(?|\)\)?|,|;/
      }
    },
    // Command Substitution
    {
      pattern: /\$\([^)]+\)|`[^`]+`/,
      inside : {
        variable: /^\$\(|^`|\)$|`$/
      }
    },
    /\$(?:[a-z0-9_#\?\*!@]+|\{[^}]+\})/i
  ],
};

Prism.languages.bash = {
  'shebang': {
    pattern: /^#!\s*\/bin\/bash|^#!\s*\/bin\/sh/,
    alias: 'important'
  },
  'comment': {
    pattern: /(^|[^"{\\])#.*/,
    lookbehind: true
  },
  'string': [
    //Support for Here-Documents https://en.wikipedia.org/wiki/Here_document
    {
      pattern: /((?:^|[^<])<<\s*)(?:"|')?(\w+?)(?:"|')?\s*\r?\n(?:[\s\S])*?\r?\n\2/g,
      lookbehind: true,
      greedy: true,
      inside: insideString
    },
    {
      pattern: /(["'])(?:\\\\|\\?[^\\])*?\1/g,
      greedy: true,
      inside: insideString
    }
  ],
  'variable': insideString.variable,
  // Originally based on http://ss64.com/bash/
  'function': {
    pattern: /(^|\s|;|\||&)(?:alias|ng-zorro-antd|@angular\/cli|apropos|apt-get|aptitude|aspell|awk|basename|bash|bc|bg|builtin|bzip2|cal|cat|cd|cfdisk|chgrp|chmod|chown|chroot|chkconfig|cksum|clear|cmp|comm|command|cp|cron|crontab|csplit|cut|date|dc|dd|ddrescue|df|diff|diff3|dig|dir|dircolors|dirname|dirs|dmesg|du|egrep|eject|enable|env|ethtool|eval|exec|expand|expect|export|expr|fdformat|fdisk|fg|fgrep|file|find|fmt|fold|format|free|fsck|ftp|fuser|gawk|getopts|git|grep|groupadd|groupdel|groupmod|groups|gzip|hash|head|help|hg|history|hostname|htop|iconv|id|ifconfig|ifdown|ifup|import|jobs|join|kill|killall|less|link|ln|locate|logname|logout|look|lpc|lpr|lprint|lprintd|lprintq|lprm|ls|lsof|make|man|mkdir|mkfifo|mkisofs|mknod|more|most|mount|mtools|mtr|mv|mmv|nano|netstat|nice|nl|nohup|notify-send|npm|ng|nslookup|open|op|passwd|paste|pathchk|ping|pkill|popd|pr|printcap|printenv|printf|ps|pushd|pv|pwd|quota|quotacheck|quotactl|ram|rar|rcp|read|readarray|readonly|reboot|rename|renice|remsync|rev|rm|rmdir|rsync|screen|scp|sdiff|sed|seq|service|sftp|shift|shopt|shutdown|sleep|slocate|sort|source|split|ssh|stat|strace|su|sudo|sum|suspend|sync|tail|tar|tee|test|time|timeout|times|touch|top|traceroute|trap|tr|tsort|tty|type|ulimit|umask|umount|unalias|uname|unexpand|uniq|units|unrar|unshar|uptime|useradd|userdel|usermod|users|uuencode|uudecode|v|vdir|vi|vmstat|wait|watch|wc|wget|whereis|which|who|whoami|write|xargs|xdg-open|yes|zip)(?=$|\s|;|\||&)/,
    lookbehind: true
  },
  'keyword': {
    pattern: /(^|\s|;|\||&)(?:let|:|\.|if|then|else|elif|fi|for|break|continue|while|in|case|function|select|do|done|until|echo|exit|return|set|declare)(?=$|\s|;|\||&)/,
    lookbehind: true
  },
  'boolean': {
    pattern: /(^|\s|;|\||&)(?:true|false)(?=$|\s|;|\||&)/,
    lookbehind: true
  },
  'operator': /&&?|\|\|?|==?|!=?|<<<?|>>|<=?|>=?|=~/,
  'punctuation': /\$?\(\(?|\)\)?|\.\.|[{}[\];]/
};

const inside = insideString.variable[1].inside;
inside['function'] = Prism.languages.bash['function'];
inside.keyword = Prism.languages.bash.keyword;
inside.boolean = Prism.languages.bash.boolean;
inside.operator = Prism.languages.bash.operator;
inside.punctuation = Prism.languages.bash.punctuation;

renderer.heading = function (text, level) {
  const lowerText = text.toLowerCase().replace(/ /g, '-').replace(/\./g, '-').replace(/\?/g, '');
  const isMarkedLabel = (level === 3) && (text.indexOf('nz-') === 0);
  const isDirective = (text.indexOf('[') > -1) && (text.indexOf(']') > -1);
  const isComponent = isMarkedLabel && !isDirective;
  const isService = (text.indexOf('Nz') === 0) && (text.indexOf('Service') > -1);
  const head = `<h${level} id="${lowerText}"><span>${text}</span>`;
  const link = `<a onclick="window.location.hash = '${lowerText}'" class="anchor">#</a></h${level}>`;
  if (isComponent) {
    return head + `<label class="api-type-label component">component</label>` + link;
  } else if (isDirective) {
    return head + `<label class="api-type-label directive">directive</label>` + link;
  } else if (isService) {
    return head + `<label class="api-type-label service">service</label>` + link;
  } else {
    return head + link;
  }
};

marked.setOptions({
  highlight: function (code, lang) {
    const language = Prism.languages[lang] || Prism.languages.autoit;
    return Prism.highlight(code, language);
  },
  renderer : renderer
});

module.exports = marked;
